1. Field of the Invention
The present invention relates to a rotary body in an image forming apparatus.
2. Description of the Related Art
Image forming apparatuses includes various rotary bodies. Photoconductors or feeding rollers are example of such a rotary body. Such rotary bodies are often removed from the image forming apparatus for the purpose of replacement or maintenance.
In the explanation given bellow, a photoconductor is used as an example of the rotary bodies.
Both ends of a rotating shaft of the photoconductor are supported by photoconductor-supporting panels provided on the image forming apparatus. In the image forming apparatus disclosed in Japanese Patent Application Laid-Open No. H10-254327, the photoconductor is housed in a photoconductor unit, and the photoconductor-supporting panels are formed on internal walls of the photoconductor unit near the ends of the rotating shaft of the photoconductor. Each photoconductor-supporting panel of the photoconductor unit includes a bearing. The bearing, i.e., an engaged member on the image forming apparatus side, is engaged with the rotating shaft of the photoconductor, i.e., the engaging member on the photoconductor side. The photoconductor is supported by the photoconductor unit arranged in the image forming apparatus, by engaging the rotating shaft of the photoconductor to the bearings of the photoconductor unit.
How the conventional photoconductor is removed from the photoconductor unit is explained below with reference to FIGS. 6A and 6B.
FIG. 6A is a schematic diagram of a conventional photoconductor unit 2000 in a state attached to a main frame 3 of an image forming apparatus. FIG. 6B is a schematic diagram of the photoconductor unit 2000 in a state removed from the main frame 3. An arrow F indicates the front side, and an arrow R indicates the rear side of the image forming apparatus. The photoconductor unit 2000 can be removed from the main frame 3 by pulling it toward the front side.
When the photoconductor unit 2000 is in a state attached to the main frame 3 as shown in FIG. 6A, a front bearing-holder 6 is in a state attached to a front panel 2b of the photoconductor unit 2000. A front bearing 7 is held in the front bearing-holder 6, and engages with a front-end projection 1e, i.e., the front-side end of the rotating shaft of the photoconductor 1. On the other hand, a rear bearing-holder 4 is in a state attached to a rear panel 2a of the photoconductor unit 2000. A rear bearing 5 is held in the rear bearing-holder 4, and engages with a rear-end projection 1d, i.e., the rear-side end of the rotating shaft of the photoconductor 1. In this manner, the photoconductor 1 is supported by the photoconductor unit 2000 by engaging both ends of the rotating shaft of the photoconductor 1 with the bearings 5 and 7 fixed on the photoconductor unit 2000.
The front bearing-holder 6 is removable from the front panel 2b of the photoconductor unit 2000 while the photoconductor unit 2000 is in a state attached to the main frame 3. To remove the photoconductor 1, an operator first removes the front bearing-holder 6, and then pulls out the photoconductor unit 2000 toward the front side (direction shown in the arrow F in the FIG. 6A). This results in the state shown in FIG. 6B. Thereafter, the operator slides the photoconductor 1 forward (toward the front side), disengaging the rear-end projection 1d from the rear bearing 5. Then, the operator lifts up and removes the photoconductor 1.
During the process of removing the photoconductor 1, if the operator mistakenly tilts the photoconductor 1 when sliding it out in an attempt to pull out the rear-end projection 1d from the rear bearing 5 for disengagement, the rear-end projection 1d also slides due to the tilting. If the rear-end projection 1d slides with respect to the rotation axis of the photoconductor 1, the rear-end projection 1d can get seized with the rear bearing 5, preventing the rear-end projection 1d of the photoconductor 1 from being removed from the rear bearing 5.
This problem is not limited to the photoconductors, but also occurs in the case of other rotary bodies. The same problem can occur in any structure that has a rotary body supported by a supporting member on the apparatus itself by engaging a part of the rotary body to the supporting member on the apparatus.